Efforts directed at improving air quality and increasing energy production from renewable resources have resulted in renewed interest in alternative fuels, such as ethanol and butanol, that might replace gasoline and diesel fuel, or be used as additives in gasoline and diesel fuel.
Methods for producing 1-butanol from ethanol are known. For example, 1-butanol can be prepared by condensation from ethanol over basic catalysts at high temperature using the so-called “Guerbet Reaction” (see for example, J. Logsdon in Kirk-Othmer Encyclopedia of Chemical Technology, John Wiley and Sons, Inc., New York, 2001).
M. N. Dvornikoff and M. W. Farrar, J. of Organic Chemistry (1957), 11, 540-542, disclose the use of MgO—K2CO3—CuCrO2 catalyst system to promote ethanol condensation to higher alcohols, including 1-butanol. The disclosed liquid phase reaction using this catalyst showed a 13% conversion of ethanol and 47% selectivity to 1-butanol.
J. I. DiCosimo, et al., in Journal of Catalysis (2000), 190(2), 261-275, describe the effect of composition and surface properties on alcohol-coupling reactions using MgyAlOx catalysts for alcohol reactions, including ethanol. Also condensation reactions on MgyAlOx samples involved the formation of products containing a new C—C bond, such as n-C4H8O (or n-C4H9OH) and iso-C4H8O (or iso-C4H9OH). They also describe, in Journal of Catalysis (1998), 178(2), 499-510, that the oxidation to acetaldehyde and the aldol condensation to n-butanol both involve initial surface ethoxide formation on a Lewis acid-strong base pair.
B. N. Dolgov et al., in Zhurnal Obshchei Khimii (1933), 3, 313-318, disclose production of BuOH by thermal decomposition of EtOH in the presence of Fe2O3.Al2O3 precipitated on carbon. Production of gaseous by-products was checked by activating the catalyst with the addition of La.
U.S. Pat. No. 5,478,789 discloses a hydrogenation reaction catalyst precursor comprising a catalyst carrier (A) and a metal oxide composition (B) carried on or mixed with the catalyst carrier (A). The catalyst carrier (A) comprises a carrier base material selected from a variety of materials, including alumina, and a coating of titanium oxide and/or titanium hydroxide. The metal oxide composition (B) comprises copper oxide, zinc oxide, and at least one oxide of a metal selected from the group consisting of an element of group IIa, an element of group IIIb, a lanthanide element, and an actinide element at specified weight ratios. Reduction of the catalyst precursor produces a hydrogenation reaction catalyst which can be used in a process for producing an alcohol by catalytically hydrogenating an organic carboxylic acid ester.
U.S. Pat. No. 5,347,056 discloses a process for producing α,β-unsaturated alcohol by selective hydrogenation of the aldehyde group in the unsaturated aldehyde starting material, using a catalyst which contains at least one oxide selected from the group consisting of oxides of yttrium, lanthanum, praseodymium, neodymium, and samarium, as a main active ingredient. The catalyst can contain, as a supplementary ingredient, a second element selected from a variety of listed metals, including calcium, strontium, and barium.
The production of Guerbet alcohols including 1-butanol has been described in the prior art. However, novel catalysts for making Guerbet alcohol products are still desired, especially those having improved activity and selectivity to desired products, which may provide economic advantages.